We use Transcat dog and cat doors, but can also customise doors for larger dogs. The most cost effective option is to replace a bottom panel window with safety glass. We measure the window exactly to size, cut a hole for the door and get the glass toughened. The glass takes around a week to manufacture, then we come back and install the glass and door.
This is just one option, dog doors can also be installed into glass opening and sliding doors. Don’t hesitate to contact us to discuss options.